Chandrayan-2 Mission

A Nandy · Post by **A Nandy** » 22 Jul 2019 15:21

Orbit better by 6000 km, will give more life to Chandrayaan 2. It did seems as though c25 was refusing to shut off

Mind boggling amount of work was done in next 24 hrs after glitch was detected.

Neela · Post by **Neela** » 22 Jul 2019 15:23

Clinical stuff from ISRO. Helium leak issue found. Communicated. Problem analysis done. Issue fixed. New launch date announced. Launched.
You wont get this even in pvt industries

VickyAvinash · Post by **VickyAvinash** » 22 Jul 2019 15:24

Congratulations ISRO. Jai hind...

A Nandy · Post by **A Nandy** » 22 Jul 2019 15:26

15 crucial maneuvers over next 1.5 months for satellite team now and then 15 mins of terror

RonyKJ · Post by **RonyKJ** » 22 Jul 2019 15:29

Successful launch and insertion of spacecraft. Dr Sivan mentioned that there was an over performance leading to a bonus of 6000 km which means that the satellite team have excess fuel available for manouvers.

Mollick.R · Post by **Mollick.R** » 22 Jul 2019 15:32

Wowww!!!!!
The naughty boy of ISRO is bringing so much glory to the parents.
3 Cheers

PS:- Did someone else noticed that on the time/velocity plotting software on top it was GSAT29 written.
?????

hnair · Post by **hnair** » 22 Jul 2019 15:35

Seems an additional 6k got added to the orbit, means lesser fuel usage by orbitre

singha, apparently you need a multiple restartable high-energy stage like khan's venerable Centaur upper-stage for injecting straight into inter-planetary journeys. Check out the difference between MOM's painstaking trajectory and khan's MAVEN. The PSLV upper stage has this capability of multiple relit in space. That capability will be slowly tested out for the CE stages too, now that there is that amazing new vaccum test facility at Mahendragiri

prasannasimha · Post by **prasannasimha** » 22 Jul 2019 15:41

Not just that but net weight injectable woyld be less with direct TLI to moon with GSLV

prasannasimha · Post by **prasannasimha** » 22 Jul 2019 15:43

Singha wrote:Apollo11 got to the moon and back in 8 days.

so why is our chandrayaan only getting to the moon in 48 days in early september.

was it because they used the huge Saturn5 rocket to make a direct beeline for the moon instead of slowly doing orbit raising manouvers ?
48 days would have needed a lot of food and o2 for the astronauts which was not feasible.

Apollo 11 could directly lift 100 tons to GTO ! Moon lander was 13 tons ! Totally different specs.
We can do TLI to moon directly but weight woild be less

juvva · Post by **juvva** » 22 Jul 2019 15:49

From the plots, there was a slight under performance of the cryo stage.This was apparently more then compensated by the longer burn to depletion.

Mort Walker · Post by **Mort Walker** » 22 Jul 2019 15:51

juvva wrote:From the plots, there was a slight under performance of the cryo stage.This was apparently more then compensated by the longer burn to depletion.

Could you post the plot here possibly? Please?

Mort Walker · Post by **Mort Walker** » 22 Jul 2019 15:57

-) 6 orbit raising burns at perigee 3, 4, 6, 11, 16, 19 (orbit changes to: 47000km apogee, 243km perigee, 55800km apogee, 71500km apogee, 89700km apogee)

-) Aug. 14 TLI burn at perigee 22 (Note. This may be Republic Day Aug. 15 in India, as it would be nice.)

-) Aug. 20 arrival initial lunar orbit (120km x 18000km)

-) Late August - 4 perilune braking burns

-) Sep. 1 arrival final lunar orbit (100 x 100km)

-) Early September - separation lander/rover (orbit change to 30 x 100km)

-) Sep. 6 - 21:28 UTC landing (Sep. 7 - 2:58am IST)

chetak · Post by **chetak** » 22 Jul 2019 16:18

prasannasimha wrote:
Singha wrote:Apollo11 got to the moon and back in 8 days.

so why is our chandrayaan only getting to the moon in 48 days in early september.

was it because they used the huge Saturn5 rocket to make a direct beeline for the moon instead of slowly doing orbit raising manouvers ?
48 days would have needed a lot of food and o2 for the astronauts which was not feasible.
Apollo 11 could directly lift 100 tons to GTO ! Moon lander was 13 tons ! Totally different specs.
We can do TLI to moon directly but weight woild be less

certainly, but we did not have the benefit of the efforts of many shady and whitewashed germans who were forced to lay the framework for such heavy-lift vehicles.

our chandrayaan is almost completely an SDRE effort.

juvva · Post by **juvva** » 22 Jul 2019 16:19

Mort Walker wrote:
juvva wrote:From the plots, there was a slight under performance of the cryo stage.This was apparently more then compensated by the longer burn to depletion.
Could you post the plot here possibly? Please?

Here is the launch video on youtube.

https://www.youtube.com/watch?v=2WO8XVWmJNQ

Please see the plots at 43:04 for example.

Mort Walker · Post by **Mort Walker** » 22 Jul 2019 16:43

chetak wrote:
certainly, but we did not have the benefit of the efforts of many shady and whitewashed germans who were forced to lay the framework for such heavy-lift vehicles.

our chandrayaan is almost completely an SDRE effort.

That's ok. Sometimes we aim for the moon, but hit London instead!

la.khan · Post by **la.khan** » 22 Jul 2019 16:44

Neela wrote:Clinical stuff from ISRO. Helium leak issue found. Communicated. Problem analysis done. Issue fixed. New launch date announced. Launched.
You wont get this even in pvt industries

Looks like ISRO practices Agile/XP/Lean/Kanban

Mort Walker · Post by **Mort Walker** » 22 Jul 2019 16:46

juvva wrote:
Mort Walker wrote:
Could you post the plot here possibly? Please?
Here is the launch video on youtube.

https://www.youtube.com/watch?v=2WO8XVWmJNQ

Please see the plots at 43:04 for example.

Just slightly. Let's see what happens when GSAT-20 is put up in Sep. The C-25 cryo engine performance will be an important step when going to the HLV.

ArjunPandit · Post by **ArjunPandit** » 22 Jul 2019 17:09

la.khan wrote:
Neela wrote:Clinical stuff from ISRO. Helium leak issue found. Communicated. Problem analysis done. Issue fixed. New launch date announced. Launched.
You wont get this even in pvt industries
Looks like ISRO practices Agile/XP/Lean/Kanban

Whatever one might question about the culture, it speaks volumes that the launch was halted in front of the president of the nation. How many of us would stop a crap project ppt in front of CTO just because some parameters were not great. Hats off to the ISRO guys. These guys should be the role models for entire generation

Mort Walker · Post by **Mort Walker** » 22 Jul 2019 17:16

Singha wrote:Apollo11 got to the moon and back in 8 days.

so why is our chandrayaan only getting to the moon in 48 days in early september.

was it because they used the huge Saturn5 rocket to make a direct beeline for the moon instead of slowly doing orbit raising manouvers ?
48 days would have needed a lot of food and o2 for the astronauts which was not feasible.

The amount of time for orbit raising could probably be trimmed as well as the time spent in lunar orbit. Moon perigee becomes an issue, but I think they could have planned a landing by Republic Day 2019. However, when this launch is nearly 10% of your annual budget, you naturally become more cautious.

Vivek K · Post by **Vivek K** » 22 Jul 2019 17:25

Great job! I could kiss the gentleman saying performance “narmal ”!

UlanBatori · Post by **UlanBatori** » 22 Jul 2019 17:27

This geeessellvee looks positively mota, not sdre at all. Amazing. As I mentioned, strap a couple more S200 boosters, increase the central tank diameter a bit, and one could lift 16T to GEO. Or stack a series of satellites in a longer tube. Is it limited by G now I wonder, from doing that.

abhijitm · Post by **abhijitm** » 22 Jul 2019 17:29

ArjunPandit wrote:
la.khan wrote: Looks like ISRO practices Agile/XP/Lean/Kanban
Whatever one might question about the culture, it speaks volumes that the launch was halted in front of the president of the nation. How many of us would stop a crap project ppt in front of CTO just because some parameters were not great. Hats off to the ISRO guys. These guys should be the role models for entire generation

This is leap beyond 'chalta hai' and jugaad mentality. This is class A perfectionist stuff. I hope people stop calling jugaad to ISRO's missions. I was deeply hurt when indian media called mangalyaan a cheap jugaad.

UlanBatori · Post by **UlanBatori** » 22 Jul 2019 17:31

When they showed the required vs. actual trajectories, it looked like Sehwag was batting with Dhawan: the trajectory was way ahead, or was I reading it wrong? At the end of course it was a Dhoniesque finish, right on time.

sudhan · Post by **sudhan** » 22 Jul 2019 17:38

Looks like them wily SDREs have imprinted the national emblem on the wheels of the rovers

The graphic before the launch showed the lil rover happily laying down some sweet tread prints with the emblem in it as it motored along..

I really hope we can have pic of those

Well done ISRO!.. make us proud!

RonyKJ · Post by **RonyKJ** » 22 Jul 2019 17:43

The plot is a bit confusing. Horizontal axis is time in seconds. White vertical axis shows rel velocity. What is the red vertical axis? Is it altitude? But it doesn't correspond to the read out. At 944.5 secs, read out says altitude is 171.4 km but graph corresponds to 550.
It would seem like under performance but Dr Sivan said over performance by 6000 km.
I have a screen grab at 42 secs but cant figure out how to embed the image here.

UlanBatori · Post by **UlanBatori** » 22 Jul 2019 18:00

sudhan wrote:Looks like them wily SDREs have imprinted the national emblem on the wheels of the rovers
The graphic before the launch showed the lil rover happily laying down some sweet tread prints with the emblem in it as it motored along..

U mean sdres are going to put Ophishial 3-lion passport seal all over lunar South Pole aka "New Xinjiang"? And call it "Greater Arunachal"?
When I saw the Lunar Chariot I realized that it could simply drive around in a circle to keep the solar panel always facing the Sun. Duh!

sudhan · Post by **sudhan** » 22 Jul 2019 18:07

UlanBatori wrote:
sudhan wrote:Looks like them wily SDREs have imprinted the national emblem on the wheels of the rovers
The graphic before the launch showed the lil rover happily laying down some sweet tread prints with the emblem in it as it motored along..
U mean sdres are going to put Ophishial 3-lion passport seal all over lunar South Pole aka "New Xinjiang"? And call it "Greater Arunachal"?
When I saw the Lunar Chariot I realized that it could simply drive around in a circle to keep the solar panel always facing the Sun. Duh!

That's what the ISRO graphic showed, not able to make the tread marks out clearly in pics of the rover.. Will have to wait and see

Vips · Post by **Vips** » 22 Jul 2019 18:22

Calling the successful launch a "historic day for India and space science", Isro chairman K Sivan announced, "GSLV Mk III has successfully injected Chandrayaan-2 in its desired orbit. In fact, the orbit is 6,000km more than what we expected. Now, the spacecraft and its team will have more life and fuel for manoeuvres.

chetak · Post by **chetak** » 22 Jul 2019 18:44

sudhan wrote:
UlanBatori wrote: U mean sdres are going to put Ophishial 3-lion passport seal all over lunar South Pole aka "New Xinjiang"? And call it "Greater Arunachal"?
When I saw the Lunar Chariot I realized that it could simply drive around in a circle to keep the solar panel always facing the Sun. Duh!
That's what the ISRO graphic showed, not able to make the tread marks out clearly in pics of the rover.. Will have to wait and see

maybe it wasn't the right angle

a_bharat · Post by **a_bharat** » 22 Jul 2019 18:45

RonyKJ wrote:The plot is a bit confusing. Horizontal axis is time in seconds. White vertical axis shows rel velocity. What is the red vertical axis? Is it altitude? But it doesn't correspond to the read out. At 944.5 secs, read out says altitude is 171.4 km but graph corresponds to 550.
It would seem like under performance but Dr Sivan said over performance by 6000 km.
I have a screen grab at 42 secs but cant figure out how to embed the image here.

Upper graph is for relative velocity where there seems to be a small under performance towards the end. The lower graph was for the altitude and was tracking as expected (170-180).

Ashokk · Post by **Ashokk** » 22 Jul 2019 19:18

Lift-off and Onboard Camera View of GSLV MkIII-M1/Chandrayaan2 Launch

chetak · Post by **chetak** » 22 Jul 2019 19:42

twitter

From a distance, it looks like a shivalingam with a third eye, above three swipes of vibhuti.

SwamyG · Post by **SwamyG** » 22 Jul 2019 19:45

Congrats Team ISRO, industry and India !!!!

ravikr · Post by **ravikr** » 22 Jul 2019 19:45

Noob Question. Why L110 shoots it to 205Kms altitude when required is 170 Kms and when C25 kicks in it starts loosing altitude while gaining RV. Please can any Gurus explain.

chetak · Post by **chetak** » 22 Jul 2019 19:59

not to forget to acknowledge

Project Director: Vanitha Mutthayya Mission Director: Ritu Karidhal

A Nandy · Post by **A Nandy** » 22 Jul 2019 20:02

https://twitter.com/isro/status/1153292272961642496

Real details in this image: https://pbs.twimg.com/media/EAFRIiyUEAY ... =4096x4096

vnms · Post by **vnms** » 22 Jul 2019 20:16

ravikr wrote:Noob Question. Why L110 shoots it to 205Kms altitude when required is 170 Kms and when C25 kicks in it starts loosing altitude while gaining RV. Please can any Gurus explain.

This is done gain RV.

sudhan · Post by **sudhan** » 22 Jul 2019 20:17

https://timesofindia.indiatimes.com/ind ... 330567.cms

Sivan also appreciated the work done by the Isro team in fixing the technical glitch that led to aborting the mission on July 15.

"We had a serious tech snag, and we fixed it. Now Isro bounced back with flying colours. Immediately after the technical snag
observed a week ago, the entire Isro team swung into action. The work that was done in the following 24 hours was mind
boggling. The vehicle was brought back to normal and the root cause of the tech snag was identified and corrected. Everything
happened in 24 hours . In the next one and a half days, the required tests were conducted to ensure that the corrections made
were proper and in the right direction. The vehicle was then handed over to the management for action.”

“It all happened because of the hard work of the team Isro especially engineers, technicians, technical assistants and support
staff… In fact, they forgot their families and sacrificed their time and ensured to fix the snag.

In fact, the expert team constituted
was on the job for the last seven days to ensure that every system functioned properly. My duty is to salute all of them," he
said.

My heroes.. each and every one of them.

We know how hard work and performing above and beyond the expectation of the job is the norm at ISRO. And when the chief says the work put in was mind-boggling.. it must have been a himalayan effort indeed..

Again.. my heroes!

These soft spoken brainy SDREs are perfect role models for India's millennials

sanjaykumar · Post by **sanjaykumar** » 22 Jul 2019 20:22

How dare India launch a mission to the moon when there are starving people in Pakistan.

UlanBatori · Post by **UlanBatori** » 22 Jul 2019 20:43

How dare India solve glitch in 24 hours when there are sooo many stupid Generals in Pakistan?